Process of aerating water in making ice.



W. B. EURKPATRICK. PROCESS oF AERATINQ WATER IN MAKING ICE. APPLICATIN HLED JULY 2l. 1915.

rm: mma/s perm: cv.. Pnumumm. wAsumnnm. n. a

meme@ Nom 23, 1915.

A A ro.

PROCESS OF AERATINGIWATER IN MAKING ICE.

specification of Letters Patent'.

Patented Nov. 23, 1915.

Continuation in part of applications Serial No.6,987, filed February 9, 1915, and Serial No. 17,617,- led March 29, 191'5. v This application led July 21, 1915. y Serial No. 41,026. l'

. This application is a continuation. in partof each of my two coending applications,

' 'Serial Nos. 6,987 and 1 ,617.

The principaldiiiiculty encountered in the practice of the aeration method in the past I is that incident to maintaining an uninterrupt'ed-low ofair until the formation of the cake of ice 'has been substantially completed.

The two principal sources of interruption '4 which are of importance in 'this connection are due to the formation of frost first .in thedrop pipe which leads air' downward tothe point Where it is dischargedl-at the bottom ofthe can, and second, the formation of i frost in the cooling pipes. Also, the formation of ice in the can sometimes closes the .'mouth of the tube and the air system is some? times blocked by the deposit. of rust, sediment and the like'.- These latter diiiiculties.

are more fully treated in the parentapplication. i A The different methods of aeratingwater in use are classified'as high and lo'w pressure. v In the practice of the hi h pressure process, lthe ainisfirst compresse to acomparatively high degree` as lfifty or sixty pounds per square inch and 'then cooled toI nearthe freezing point to dehydrate it, When-it is again permitted toexpand toabout eighteen to twentyLve pounds, the high pressure be-A `ing usedv to getefXcessive dehydration.` From this point the air pressure is again reduced' A by throttling and .the` air is led through a pipe'in the corner vof the freezing can, or

otherwise-in contact with or in close proinrnl ity to fthe brine, to the bottom ofthe freezing can nea-r the center Where the air is released.- This apparatus is subjectto frequentstoppage 'owing to the formation of frost' 1n thedrop pipe and .in the air cooling vcoils as just described. Also the compression of the air to fty or sixty pounds which is incident tothis process is expensive.

The principal objection to'the low pressure vmethod in which. the pressure 1s' only sufficient to keep the Water in agitation and,

p Whichis therefore less expensive is that the passage of the air upward throughthe can is,in the natural course of things, certain to become blocked by the formation of ice. In the"applicants invention under discussion,

the passageof the air upwardthrough the connection. with this cooling system, I so deliver the .air at the bottom of the cans that 'it is not cooled below the freezing point until the formation' of the cakejjofice is practically complete. This greatly re uces the formation of Afrostin the drop pipe and renders the excessive dehydration `practised in the high pressure system wholly unnecessary7 for. 4it will be understood that the high pressure Tand low temperatures used arefor the purpose of precipitating as much moisture as possible from the'air and to. thus overcome in a dierentvway l.the tendency-to choke the droppip'e withfros-t. 4In this'connection it will be noted that thehigh pressure system had always been' used with the delivery pipe passing .in l close proximity to thel brine, the

temperature of which is usually about 14 v Fl, 'while the delivery pipe in the present "instance is near the center'of the body of Water to be frozen so that it does not come in contact with temperatures sufficiently low to freeze'the moisture in the air until the formation" of the cake is complete, or nearly complete.' "By combining this feature .with

the dehydration produced by cooling withclear Water-at low temperatures, obstruction by lfrost is avoided, both in the drop pipe" and ,the cooling' coils.

,-By thus avoiding the necessity for excessive dehydration and providing acooling means which cannot clog, and by other features hereinafter referred to, I have'reduced the expense incident to compressing the a1r and increased the eiiciency of the-operation.-

g slotted throughout its entire length as at h In the'acoompa'nying drawings, I have illustrated so much of my apparatus for aerating water in the manufacture of ice,

`as is necessary to complete understanding of the invention.

Figure 1 is a vertical section of a portion of a brine'tankshowing a number of' cans in section' and the, drop pipes andsupply pipes jin elevation; also the air' cooling devlice in elevation; and F ig. 2 lis a section on the line 2, 2l of Fig. vl, showing the cooler in cross section. n

Referring to the` drawings by numerals;

the apparatus as shownincludes va cooling coill having an inlet 2 to which air is supplied at a medium pressure, .preferably from twelve to -twenty-five pounds above atmosphere, and an outlet 3 tothe header 4: of the system, by means of whichl the air for aerating the Water is delivered .to the cans. The. cooling apparatus 'also 'includes an ammonia coil 5, the helices of the ainn'ionia coil being arranged in -a vertical plane .as are those of the air coil, the. latter being placed directly under the former, as

shown in cross section in Fig. 2, s0 that all the pipes 'o f each cooling unit are in a single vertical plane. The inlet^ 6 of the. ammonia coil-is at the bottom, andthe outlet 7 at the top.

, Just over the ammonia coil, I provide a- Water delivery pipe 8 which is preferably 9 or otherwise provided with suitable orifices to discharge Water and permit it 'to flow uniformly over' the entire coil. i Wateris supplied to the vdelivery or sprinkler pipe 8 by a pump 10 or other suitableand convenient means, either taking they -Water from the catch basin 11 beneath the coils'or from an. outside source "by Way of the pipe 12.

'An important feature of the cooling system resides in .the use of-purevvvater in` stead ofy brine or the equivalent asa cooling medium in connection with the ammonia and' air coils, and of valves,l either automatically or manually operated at 13 and `let by means .of which thepressure 'and expansion of the ammonia lvapor-may be so regulated asto give the desired temperature, buteven A in the absence of such regulation 'of the 'pressure 4of the ammonia vapor, the air pipes cannot` be cooled below freezin'gbecause the cooling effect lis transferred `from fthe ammonia pipes to the lair pipes by means of fresh water, flowing inafilin by gravity from the amnioniato the air pipes, and this 'iioiv could notofcourse -bemaintained at I freezing temperatures. Substantially pure Water having the saine freezing vpointas pure Water-.may be used With thesa'ine result. Under thesecircumstances 'it is pracy ticzlly impossible lto reduce the temperature lof the :air to a poin't lowerthan ive -or six degrees Fahrenheit above the freezingpoint and at this temperature, the tubes cannot become stopped With frost. The temperature of the air in the dehydrater may go much higher Without detriment to the operation of the plant.

- An importantfeature of my method consists in the handling and delivery of the air for agitating the Water at temperatures well above freezing. The most convenient Way of doing this is byusing clear Water as a heat transfer medium in the deliydrater but other means for cooling the Water and dehydrating itl may be employed Within the scope ofmy invention. The use of clear Water for this purpose is one feature only of several Ainvolved in the method which is the subject of the invention.A As I havestated, the air'passes through the cooling coil at. a medium pressure which may be lvaried from' twelve 'to twenty-five pounds above the atmosphere, but at this pressure with average humidity, a considerable amount -of'conden'sation takes place and the moisture thus condensed may be removed by a suitable trap or drip of commercial variety, shown at 15.

" In Fig. 1. at the left', I have shown a portion of a brine tank '16 of thel type oommonly used-in the manufacture of can ice,

1 together with a number of cans 17 in operative position for freezing. The area occupiedby the tank is traversed by headers 4 leading from the cooler. From the header l a lateral extends outward between'each ltvvo lines of cans and inserted in each lateral between each pair of cans is a four-way fitting, or cross 19 which inav contain a reducing valve or orifice by which the normal air pressure is dropped to a point slightly above atmosphere, as shown and described inimy o o-pending application referred to. Tivo arms'of each cross-fitting 19 preferably extendalong the sides of the adjacent cans .to a 4 point near the center and the air is led by suitable means as the connection 22,

Ashown in Fig. 1, to the drop pipe 21 which discharges the air at the bottom near the center of thev4 can. The drop pipeivhich l use'is straight so that it may be convenof a steam nozzle by moans of which it may be" released. and then being perfectly straight may be c onvenientlir withdrawn.

While the pipe as shown does not occupy Limpie that obstruction of the drop pipe by frostl when delivering air, cooledas described herein by lthe flow of clear water over the air cooling coil., 1s not an element which need be taken into account in the conduct of the plant. The vadvantages o'f the inclined pipe arranged as described, `are fully set forth in my co-pending application No. 17,617, and need not be enlarged upon in this specification.

lVhile the preferred method of protecting the air pipe from the low temperature of the brine is by passing the drop pipe through the body of water to be frozen keeping it well away from the sides 'of the can, the' pipe may be otherwise protected from the low temperature of the brine, Vthus accomplishing the method of my invention, by other means obvious to those yskilled in the art, though these devices are considered less practical than that specifically described.

The operation ofthe system will be described in Vconnection with .the process oi my invention. Starting with the cans filled with waterand the drop pipes in position as shown in Fig'. 1. theconnections being made from 'each cross-fitting 19 to the corresponding drop pipes 21 by means of-a hose or flexible tube ammonia is applied to the coil o by way of the inlet G. Air at medium pressure, determined as sufiicient to keep the air passage. to the can open until freezing is complete` is applied to the coil 1 by Way of the inlet Zand fresh water is passed over the ammonia andairl coils-as indicated. The temperature Vof the air pipes is controlled and kept above freezing by using clear water as a heat transfer means, fresh water serving to prevent the reduction of the'temperature of the air to an extent` sufficient to 1 cause frost .in the pipes."'1`.he water which may be condensed bv 'this drop inpressure,

the quantity depending upon the humidity of the air. there being none under some con ditions` is removed from the drip 15 and the cooled air is delivered to the header 4 whence it -is distributed b v way of crosses 19 and the, drop pipes .21. It will be understood that the initial pressure at the inlet 2 is substantially maintained throughout the system as far as the reducing orifices referred to herein and described in the currentapplication. Ajt this point ,the air is expanded and throttled down to a. pressure slightly above atmosphere, for a higher pressure would interfere with freezing and would blow the. water from the cans;

To keep the passage 4e of the drop pipe from being closed by the ice formed in. the can in the regular process of freezing, the full initial pressure is sometimes necessary. This is obtained bythe simple expedient of permitting the air which escapes to back up until it reaches the .pressure of the coil or inlet o-r becomes` sufficient to open the pas sage through theice.

In practice it 'is found that with twelve or fifteen pounds pressureat the air inlet, the drop pipe, constructed as described, will keep open until the ice cake is complete. If any obstruction takes place, this is cuickly broken b y the'rise of pressure.

It will alsobeapl'iarent that by the use of a cooler for the compressed air, using clear water as a neans for abstracting the heat from the ai which prevents the formation of frost in tie cooling coil, combined with a drop pipe w lich isprotected from the lower ten'n'ieratures by being placed near the center of the can, I have rendered the use of high pressures to produce excessive dehydration unnecessary for formation of frost in the drop pipe is practically eliminated. -r

This also results'in greatly increased economy and a system of unparalleled efficiency in that obstructions4 of the air pipe,resulting in white ice,- are Jso infrequent that a practically uniform product of the highest qualitv is produced with the least `expenditure for labor'and' attendance.

-I have t-hus described the method which is the subject of my invention specifically and in detail in order that its nature and operation may be fully understood; however, the specific terms herein are used in theirdescriptive rather than in their limiting sense and the scope of the invention is defined in the claims.

vI claim:

' 1. A-process of agitating water by air in making ice which consists in compressing the air to a pressure in the vicinity of from twelve to twenty-five pounds above atmospliere. dehydratin-g the air by cooling it, re ducing the pressure, passing such air through the mass of water to be frozen following apathnear the center, and delivering air into the mass of water at the bottoni.

2. A process of agitating water by air in making ice which consists in compressing the air to a pressure ofv from twelve to twentylve pounds above atmosphere, dehydrating the air by cooling it to a temperature well above freezing. reducing the pressure to a point slightly in excess of that `of the atmosphere. lpassingir such air through or near the center of the water to be frozen, anddeliy'ering it to the Water near the bottom of thel mass.

3.. A process of agitating water by air in the manufacture of ice which consists in compressing the air to a pressure of from twelve to twenty-five pounds above atn1osphere, dehydrating the air by cooling it using substantially clear water as a heat transfer medium, reducing the pressure and passlng the 'air through or near the' center of the mass of water to be frozen, and delivering the air near the bottom of the mass ofl water.

4. A process of agitating Water by air in making licewhich consists in .compressing l the air, dehydrating the air by cooling it using substantially clear water as a heat transfer medium, reducing the pressure, passing such air through or near the center ofthe mass of water to be frozen and de# livering such air into the bottom of such mass of Water. l

5. A process of agitating water by air in making icev which consists of compressing the air to a pressure in the vicinity of from twelve to twenty-live pounds above atmosphere, cooling the air to 'dehydrate it, the temperature being maintained at least five or six degrees above freezing, reducing the pressure so that it is slightly in excess of that of the atmosphere, passing such air through or near the center of the mass of water to be frozen and' delivering it`near the bottom of the mass of Water.

6. A process of removing moisture from compessed air' in the manufacture of ice which consists in' circulating practically pure Water in indirect heat-exchange with a refrigerant, bringing such Water into indi,

rect heat exchanging relation with the compressed air whereby a portion of the mois ture in said air is condensed, and then separating such condensed moisture from the air. 7. A process of agitating Water by air in the air, dehydrating the air by cooling it to a temperature at least five or six degrees 'the air.

9. A process of manufacturing ice which vmaking ice which consists in compressingconsists in freezing the Water in cans in a non-freezing liquid, as brine, at a temperaagitating the water by air by compressing the air, and dehydrating the air by cooling it to a temperature at least five or six degrees above freezing, leading it to and introducing it into the mass of the Water, near the bottom, the air being protected in its passage from the temperature of the brine.

Signed by me at Baltimore, Maryland i this 20th day of July 17th, 1915.

WILLIS B. KIRKPATRICK.

Witnesses:

HAROLD TsoHUDI, M. B. WEBNER.

copies 0f this patent may be obtained for ve cents each, by addressing the Commissioner of Patents. Washington, D, 0.,

ture well below the freezing point of Water, 

